In conventional circuit switched domain services, a subscriber may subscribe to at least one of multiple called side services, such as call waiting, call forwarding unconditional, call forwarding busy and call forwarding no reply. The multiple called side services provide for incoming calls different called side contact manners of forwarding and waiting. The multiple called side services are independent of each other and their trigger points are set as the following three: the called party being busy, the called party giving no answer and without conditions, which cover limited application scenarios, e.g., a scenario that the subscriber hopes to forward a call during meeting is not covered.
With the development of voice services over packet switched domain, a call intelligent routing service has emerged currently. The call intelligent routing service is customized by a subscriber in advance, and provides different forwarding patterns for incoming calls based on subscriber presence information, such as serial call forwarding, parallel call forwarding, call forwarding to voice mailbox, and call information converted to text information. The subscriber may publish his presence information, such as “I'm in a meeting”, in a packet switched domain through network messages such as the Session Initiation Protocol (SIP) PUBLISH message. The scenario that the user hopes to forward the call during meeting is thus fulfilled. However, the inventor of the present invention finds that there are still disadvantages below of the conventional technical scheme.
Firstly, called contract modes provided for incoming calls are mainly limited to call forwarding services and do not cover other effective routing contact manners such as call waiting, queue, and call record converted to email. Therefore there are few routing contact manners.
Secondly, there is a lack of the call intelligent routing service for user groups, e.g., a Centrex group and a pickup group, there is no more than one intelligent routing policy based on different called attribute identities such as a called number or a group number to which the called party belongs either.
Thirdly, the subscriber presence information, as one of the trigger conditions for intelligent routing, includes explicit presence information and implicit presence information; the former is the presence information published in the network by the subscriber in certain manner, while the latter is the natural presence information of the subscriber terminal in the network, such as the device connection status, service applications, and network locations and types. However, not all the possible implicit presence information can be fully used currently, and it is hard for the subscriber, while customizing services, to precisely describe a status of the subscriber when an intelligent routing service is triggered.
Moreover, all conventional messaging services, such as Instant Messaging (IM), Short Message Service (SMS), a Multimedia Messaging Service (MMS), email, voice mail, fax, and paging messaging, have their own application networks respectively. In order to effectively unify these messaging services, a unified messaging service has emerged in the industry. The unified messaging service integrates the messaging services which were previously carried out respectively through networks such as the telephone network, the paging network, the mobile network and the Internet, such that a subscriber may receive messages from various messaging services in any manner, for example, a voice message may be sent through email as the attachment of the email.
To be brief, a unified messaging system may be regarded as an integrated mailbox which may store and forward information of all types from various terminals, including the instant messages, short messages, multimedia messages, email, voice massages, fax and Paging messages. A subscriber may send and receive all these messages anywhere and anytime through devices such as a telephone, a fax machine, a personal computer (in communication with the Internet), a cell phone and a pager.
However, applications of a unified messaging service are still limited because the unified messaging service focuses on the conversion between different types of messages and provides a system framework application that is comparatively fixed, e.g., a unified messaging email box may be provided for the subscriber and all the information received is converted into email to be sent to the subscriber. There are not comprehensive pre-customized intelligent routing policies for all types of messaging services above, for example:                the conversion of various incoming messages is a main service provided, while no other effective contact manner, such as message forwarding or message converted to call, is provided;        the unified messages may not be processed based on all possible presence information of the destination subscriber, and there is no effective conjunction with other related applications, e.g., the presence information may not be in conjunction with real-time call control; as a result, classified demands of the subscriber may not be satisfied, e.g., the subscriber may wish a short message sent from his family to be converted into a voice call that may be answered through an onboard mobile phone while he/she is driving and is unable to check a short message;        the unified messages may not be processed for user groups including the Centrex group and the pickup group, and there are not intelligent routing policies based on different called attribute identities, such as a called number or a group number to which the called party belongs.        